Aza-aromatic hydrocarbons are potentially hazardous environmental pollutants. Some of them have exhibited carcinogenic and nutagenic activity. Many of them have not been positively identified. Their structure is speculative. The objective of the proposed research is to prepare aza-aromatics with known structure to aid in the positive identification of the environmental contaminants. The compounds prepared will be evaluated in a nutagenic screen (Ames assay). Compounds that are strongly mutagenic will be further evaluated in a mammalian cell culture (hamster embryo) as an additional measure of potential carcinogenicity.